1. Field of the Invention
The invention relates to display technology and more particularly to electrowetting displays and fabricating methods thereof.
2. Description of the Related Art
Generally, in a so-called electrowetting technology, electric voltage is applied to a polar liquid acting as an electrolyte, causing the surface tension of the polar liquid to change. Electrowetting technology is applied to displays. For example, hydrophobic insulators, electrodes, polar liquids, and nonpolar liquids are disposed and limited in a pixel region, and electric voltage is applied to the polar liquids, causing the interface tension between the polar liquids and hydrophobic insulators to change. Thus, causing the nonpolar liquids to move or agglomerate backward. The reflective light varies due to motion or agglomeration of the nonpolar liquids. Thus, allowing colors displayed by displays to be adjustable.
In the electrowetting displays disclosed by the subsequently listed patent publications 1 and 2, separators between each pixel do not completely support the gap between the upper and lower substrates for one single pixel range. When applying the technologies to flexible displays, at flexed portions, the problem of polar liquid overflow potentially occurs from one single pixel to a neighboring pixel.
In the electrowetting displays disclosed by the subsequently listed patent publication 3, closed structures are utilized for each pixel, but greater height (high-wide ratio) of the separators is required, resulting in increased processing difficulty. Further, the disposition processes of the nonpolar liquids is not compatible with cheaper and simpler dip-coating processes, potentially increasing process cost and decreasing process yield.
In the electrowetting displays disclosed by the subsequently listed patent publication 4, a device for holding the nonpolar liquids at a position where the nonpolar liquids agglomerate backward, is capable of improving the display quality of electrowetting displays. However, practical implementation of the process for devices is difficult, also potentially increasing process cost and decreasing process yield.
Above mentioned patent publications are as follows:
1. WO 2005/098524;
2. WO 2006/017129;
3. US 2006/0132927; and
4. US 2005/0151709.